Contact lenses have been used commercially to improve vision since the 1950s. Conventional lenses typically are made of so-called “hard” or “soft” materials. Soft contact lenses have been developed as drug delivery devices for the ophthalmic environment wherein the pharmaceutical agent is added to the packing solution that is contained in the contact lens package. The contact lens absorbs the pharmaceutical agent and then delivers the agent to the ocular environment when the user wears the contact lens. As well, the lens package may encounter microbes, and lead to infections of the lens wearer. To address the issue of microbial infections, antimicrobial agents, have been added to contact lenses, as for example in U.S. application Ser. Nos. 10/028,400, 10/029,526 and 60/428,620, the disclosure of which all are hereby incorporated in their entireties by reference. The pharmaceutical or antimicrobial agent may be incorporated into the body of the lens, coated onto the lens surface, or included in the lens packaging solution. In this way, it is envisioned that the package would allow greater uptake of drug from the lens without the drug inadvertently being absorbed (or adsorbed) into the package itself.
Conventional contact lens packages are composed of a molded plastic base and a sheet overlying the top of the base. The cover sheet typically is a foil sheet laminated with a bottom layer of another material that is similar in composition to the molded plastic base. While sealing the contact lens packages with the laminated foil sheet, the two like materials are heat sealed together to provide a tight seal.